NAME    [Toc]    [Back]

       form_hook - set hooks for automatic invocation by applications

SYNOPSIS    [Toc]    [Back]

       #include <form.h>
       int set_field_init(FORM *form, void (*func)(FORM *));
       void (*)(FORM *) field_init(const FORM *form);
       int set_field_term(FORM *form, void (*func)(FORM *));
       void (*)(FORM *) field_term(const FORM *form);
       int set_form_init(FORM *form, void (*func)(FORM *));
       void (*)(FORM *) form_init(const FORM *form);
       int set_form_term(FORM *form, void (*func)(FORM *));
       void (*)(FORM *) form_term(const FORM *form);

DESCRIPTION    [Toc]    [Back]

       These functions make it possible to set hook functions  to
       be called at various points in the automatic processing of
       input event codes by form_driver.

       The function set_field_init sets a hook to  be  called  at
       form-post  time  and  each time the selected field changes
       (after the change).  field_init returns the current  field
       init hook, if any (NULL if there is no such hook).

       The  function  set_field_term  sets a hook to be called at
       form-unpost time and each time the selected field  changes
       (before the change).  field_term returns the current field
       term hook, if any (NULL if there is no such hook).

       The function set_form_init sets a hook  to  be  called  at
       form-post  time  and  just  after a page change once it is
       posted.  form_init returns the current form init hook,  if
       any (NULL if there is no such hook).

       The  function  set_form_term  sets  a hook to be called at
       form-unpost time and just before a page change once it  is
       posted.   form_init returns the current form term hook, if
       any (NULL if there is no such hook).

RETURN VALUE    [Toc]    [Back]

       Routines that return pointers return NULL on error.  Other
       routines return one of the following:

       E_OK The routine succeeded.

       E_SYSTEM_ERROR    [Toc]    [Back]
            System error occurred (see errno).

SEE ALSO    [Toc]    [Back]

       curses(3), form(3).

NOTES    [Toc]    [Back]

       The header file <form.h> automatically includes the header
       file <curses.h>.

PORTABILITY    [Toc]    [Back]

       These routines emulate the System V forms  library.   They
       were not supported on Version 7 or BSD versions.

AUTHORS    [Toc]    [Back]

       Juergen  Pfeifer.   Manual  pages  and  adaptation for new
       curses by Eric S. Raymond.